The effect of inhibiting fatty acid oxidation with (plus) octanoylcarnitine in perfused rat livers under various physiologic and pathologic circumstances was evaluated. These studies clearly showed that such inhibition markedly increases hepatic triglyceride synthesis and secretion into the perfusion media. The hepatic triglyceride was secreted as a particle whose density was less than 1.006. BIBLIOGRAPHIC REFERENCES: Raskin P., Aydin, Ismet, Unger, Roger H. The effect of insulin on the exaggerated glucagon response to arginine stimulation in diabetes mellitus. Diabetes. 25:227, 1976. Raskin, P., Futia, Yoshikuni, and Unger, Roger H. Effect of insulin-glucose infusions on plasma glucagon levels in fasting diabetics and non-diabetics. J. Clin. Inv. 56:1132, 1975.